drz 400 not charging battery...

Greetings all, new member, long time lurker...

First things first, I have read the FAQ about charging system diagnosis/free power mod.

Anyways, my '05 S would not start last week w/ the button while I was out trail riding near my home. I bump-started it and got it home no problem except for a few stumbles when rolling on the throttle hard. I did the checks and the stator appeared good. The battery was not getting 14.5 volts at 3k however. I borrowed a buddy's battery and checked all the connections. They appeared good. I even replaced the blade fuse at the battery. I put the volt meter across the battery w/ the bike running, and presto!, 14.5 volts!

Cut to this weekend. I'm riding about 20 miles from home and stop to grab a drink at a gas station. I come out and hit the button...nothing. I figure I can make the 20 mile ride off the stator alone, and sure enough, 10 miles to go, the bike starts to sputter/pop and dies on the side of the road. Panel LCD is dead, nothing.

I get it home and grab a new battery, check the voltages and ohms everywhere again (except at the rectifier/regulator) and everything appears good except at the battery where it's only 12.4 volts running. I'm not getting any charge. I check the fuse and it's good, the wiring appears good, the stator puts out 70 or so volts a/c when running and ohms out at about 1.2/3 when not. There is no continuity when checked to ground either. As I am not confident in my ability to check the r/r on my own, I will remove it and have a competent friend check it out. With that said, is it possible the r/r COULD test good (like when it did last week) and then die right after? I know these things can be finicky, especially when hot, but I just checked w/ the bike cold and it's not getting 14.5volts. I know this all sounds like a newb question, but it's driving me crazy trying to figure this out, ESPECIALLY after it was getting a charge last week.

What say you TT'ers?

the free power mod as decribed in the faq where you read the diag procedure.

To me it sounds like the reg/rec is dodgy or could be cable/continuity problems to the reg/rec (check all cables and connectors)

I say this because it's strange you weren't getting 14.5V across the battery one minute.

Then when you swapped the battery, you did.

You can also check the generator by starting the bike, disconnecting the reg/rec and checking each phase (yellow wires from the generator) with the meter on AC volts. One probe on one of the generator outputs, the other to earth. You should get, if I remember rightly somewhere between 15 and 70 Volts.

i think it might be the connection between the r/r...I can't get it apart by hand and bet it's corroded, acting as a switch...any tricks to seperate this connector (the one with the red and red/black wire seen in this picture)


cbr9- Uh, no. Check stator output like in FAQ. if you get significant voltage between a yellow wire and ground you have a problem.

grand - You have been comprehensive in your checks but don't loose hope. Start from scratch again. Verify stator output, ohms and shorts. Check the connections again, stator to RR and RR to wire harness and the connection between the fuse holder and the BAT. Clean and check the BAT terminals. Replace the fuse again. If the connection at the blade fuse was poor once, it is probably still poor. The fuse holder may need replacement. If the stator is good you should be able to get charge voltage at the battery even if lower than desired. Then to "Free Power".

Although RR failure is rare, it can never be counted out as a possibility. It is fairly easy to check the diode bridge. Quite difficult to check the voltage regulator part. Not on A DRZ but I have had RR that were intermittent so that is a rare but possible failure. I was told it could not happen but I'm here to tell you it can.

If the stator is good, I"ll bet you find the problem in the wire connections.

Yea. You disconnect it with a pair of wire cutters and do the free power mod. (disconnect the BAT first). That connection is the whole point of free power.

I got it apart and it def appears that one of the spades had some melted plastic on it from the connection...looks like it's time to hard wire...

that is what the free power mod is.

real quick...I'm going to do the free power mod, but what do you do to the wiring that goes into the harness? Do I just shrink wrap the cut end and let it hang? What I mean is what about the wiring that runs into the harness after the faulty connector? After it's cut, what happens? Can I or should I remove it?

Yes, shrink wrap the ends and forget them.

What could cause my 02 Suzuki drz400 not to charge. When my battery is charge I can ride for 2 days and then the battery is dead. I checked my wires. They are good. Took the hot off my battery when was running(heard if it dies then it's a bad stator) didn't die. I noticed when I was riding at night when I'm on the gas the lights dim and when I hold in the clutch the lights get brighter. Please help

You should go to FAQ and follow the electrical troubleshooting guide.  Removing the battery from the circuit is not a sure fire way to test the stator.  The stator is 3 phase.  It can loose a phase and not keep a battery charged but still run the motorcycle.  I personally lost a stator, battery would not start the bike, disconnected the headlight, push started, rode it 200 miles home and the battery was fully charged when I got there.  Removal of the headlight load allowed the voltage to rise enough to charge the battery.  Stator was on its way out but not completely gone.

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